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A079407 Numbers n such that the least s>=0 such that sum(k=0,n,(k+s)!/C(n,k)) is an integer satisfies s=n-1. 0
1, 2, 4, 5, 13, 17, 19, 23, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..33.

FORMULA

Seems that sequence consists of 1, 2, 4, 5, 13, 17, 19, 23 union primes >=31

PROG

(PARI) for(n=1, 150, s=0; while(frac(sum(k=0, n, (k+s)!/binomial(n, k)))>0, s++); if(n-s==1, print1(n, ", ")))

CROSSREFS

Sequence in context: A102932 A128457 A139485 * A078652 A289491 A102992

Adjacent sequences:  A079404 A079405 A079406 * A079408 A079409 A079410

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Feb 16 2003

STATUS

approved

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Last modified March 30 12:10 EDT 2020. Contains 333125 sequences. (Running on oeis4.)